This proposal is for continuation of a 15 year long, prospective high risk family study involving a community sample of 442 alcoholic and nonalcoholic families (1901 individuals). The study spans preschool to late adolescence for the core group of male and female offspring being followed (n=468),and the new work would move the study into early adulthood. Both biological parents (ages 22-55) and 514 other offspring are also being followed. 89% of families continue to take part. Family members are evaluated at 3-year intervals using a multidomain protocol of behavioral, psychiatric, psychosocial and cognitive measures, as well as measures of the social environment. The latter are hypothesized to affect risk via modeling, reinforcement, opportunity access, and cueing. To better establish onset of drug use and problems, yearly assessments on 11-17 year olds are also done. The study's long term goals are (1) identification of risk and protective factors for the emergence and development of alcohol and other substance use disorders (AUDs & SUDs) among offspring, with a special focus on the interaction of individual and contextual factors in the development of risk aggregation and in the prediction of AUD onset. The new project period is the first during which these relationships can authoritatively be tested since the interval of late adolescence to early adulthood captures the time when high rates of substance abuse appear. Aims are to identify the proximal and distal predictors of onset and course (trajectory) of initial alcohol use, the progression into drinking problems, other drug involvement, and AUD, and to identify the social environmental factors that mediate or moderate these relationships. Of special interest is the detection of different trajectories of risk, and establishing their differential relationship to substance abusing and collateral life outcomes. (2) A second goal is the delineation of (a) risk and protective factors for chronicity and remission of SUDs among the parents, and of (b) the relationship of parental factors to offspring developmental outcomes. Aims are to identify the predictors of moving into and out of AUD diagnosis, and the delineation of collateral psychosocial and health outcomes. A special focus is the moderator role of the marital/intimate partner relationship. The project is one of the developmentally earliest high risk for AUD prospective studies extant, and the only one currently that would span preschool to early adulthood. It has the unique potential to detect early childhood predictors of AUD/SUD outcomes, and to evaluate the relationship between these distal and more proximal risks. Findings will have major relevance in more precisely specifying the targets and timing of preventive interventions.